Question: I would like to know where I can find information on a Dante gas shut-off valve which is installed in the floor next to a gas fireplace. I need to know what it looks like and how it is installed. Any information you can provide would be appreciated. Molly Davis-Bright Answer: These are simply gas valves that are installed underneath the floor. A brass plate serves as a decorative finish at the floor or wall, and a key turns the valve on or off. They are available in 1/2" and 3/4" sizes and come in "straight thru" and "angled" models. Not much else to them.